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Description
Poor or slow speeds can be caused by:
- Host device port speed.
- Format and file system.
- Directory with lots of small files.
- Deeply nested directory.
- USB cable too long.
- Not enough free space on the drive.
- Connected to slower USB port.
- The host does not have enough cache.
- The cache is not optimized.
- To many background programs.
- Multiple connections to the computer.
- Outdated drivers.
Resolution
USB Standard and Speeds
Version | USB Interface Speeds | Ports |
---|---|---|
SUPERSPEED USB 20Gbps USB 3.2 (Gen 2x2) |
20 Gb/s (2500 MB/s) |
USB Type-C, USB Type-A, etc. |
SUPERSPEED USB 10Gbps USB 3.2 (Gen 2), USB 3.1 (Gen 2) |
10 Gb/s (1250 MB/s) |
USB Type-C, USB Type-A, etc. |
SUPERSPEED USB 3.2 (Gen 1), USB 3.1 (Gen 1), USB 3.0 |
5 Gb/s (625 MB/s) |
USB Type-C, USB Type-A, etc. |
HI-SPEED USB 2.0 |
480 Mb/s (60 MB/s) |
USB Type C, USB Type-A, etc. |
USB 1.1 | 12 Mb/s (1.5 MB/s) |
USB Type-A, USB Type-B, etc. |
Need more help?
Answer ID 5043: USB Interface Standards and Theorectical Speeds
Host Device USB-C Performance Specs
The speed of a drive depends on the port used.
Some systems have USB-C ports that work with different USB drives.
Solution: Check the host device to confirm specs of the USB-C port.
Performance Best Practices
- Directory and File Sizes (Lots of small files)
The total amount of data on a disk and the size of each file can result in slow speeds.
Information: A large number of files saved in a single directory will transfer faster than the same number of files spread across multiple directories.
1 TB of large files will transfer much faster than 1 TB of millions of small files. |
- Windows and macOS File System
Drives are formatted as NTFS, FAT32, exFAT and HSF+. File systems like NTFS on Windows and APFS on macOS perform better than exFAT, FAT32 and HSF+
Solution: Format the drive with the native OS file system.
-
- Windows: format as NTFS
- macOS: format as APFS
Need more help?
- Windows Write Caching
Some drives need this turned on to get the best results.
This improves speeds by collecting commands sent to the drive.
IMPORTANT:
Loss of data can occur when Write Caching is turn on.
It can happen during data transfer if there is a sudden loss of power or hard shutdown of the computer.
Need more help?
Turn on write caching.
- Connect the drive.
- Press the Windows Key + X.
Click Device Manager. - Expand Disk Drives.
Right-click the drive.
Click Properties.
- Click Policies.
Click Better performance.
Click Enable write caching on the device.
Click OK.
- Windows 10 Real Time Protection
Doing a scan with this tool may cause slow speeds.
Solution: For a short time disable this tool.
Need more help?
Microsoft Article: Turn off antivirus protection in Windows Security
- Connect to a Different Computer
Slow speed may be caused by the computer.
Solution: Test the drive on another one.
- USB Hubs and Extension Cables
These can slow the drive speed.
Solution: Connect the drive directly into the system.
- USB Port and Cable
Slow speeds can be caused by plugging into a slow or faulty USB port.
Solution:Use a high quality USB cable.
- Confirm USB Type used by USB-C Port
Different types of USB use the USB-C port.
Solution:Confirm USB-C speeds offered by the systems USB-C port.
Contact the computer or motherboard maker for support.
- Drive Space Available
Performance can decrease when drives are close to capacity.
Solution: Make sure the drive has 10% to 15% space free for best results.
- Laptops and Portable Computers
Make sure the computer has at least a 75% charged battery or is plugged in.
Solution: Adjust the power mode or Energy Saver Settings.
- System Memory
Small amounts of memory may not have enough resources to process data. This can result in slow backups.
Solution: Stop apps and software that use high memory.
- Computer in use during Speed Tests
Using the computer when running a speed test can use higher than normal CPU and memory.
Solution: DO NOT use the computer during these tests.
- Fragmented Disk
This may cause slow disk read.
Solution: Defragment the disk.
Need more help?
- Microsoft Article: Run the System File Checker tool.
- Microsoft Article: Defragment your Windows 10 PC
- Apple Article: How to repair a Mac disk with Disk Utility
- Anti-Virus, Anti-Malware and End Point Protection Software
These tools scan incoming TCP/UDP packets which cause slower data transfer rates.
Solution: For a short time stop these softwares when moving data.
- Infected Computer
A computer with virus or malware may cause slow speeds.
Solution: Make sure that the system is virus, trojan, and malware free.
- Microsoft Article: Change the power mode for your Windows PC
- Apple Article: Change Energy Saver preferences on a Mac desktop computer
- RAID 0 vs RAID 1
RAID 0 offers the fastest read/write speeds but does not provide data protection like RAID 1.
Solution: Configure a device as RAID 0 for the best speeds.
- CPU (32 bit vs 64 bit)
Older 32 bit CPU systems may not have the power to handle modern technology.
Solution: Stop apps and software that use high CPU and memory.
- Outdated Motherboard Chipset or Drivers
These can affect system speeds.
Solution: Make sure that the motherboard chipset and drivers are up to date.
Contact the computer or motherboard maker for support.
Drive Diagnostic Tools
- Windows:
- Microsoft Article: Run the System File Checker tool.
- Microsoft Article: Defragment your Windows 10 PC.
- macOS:
- Western Digital Software: